Between Eumelanin and Pheomelanin there are a wide range of skin tones.

This range is due to a dominant Sulfuric presence in Pheomelanin and a dominant Selenium presence in Eumelanin which could explain the differences in smell 🤔

Scientifically, there are six categorical types of melanin in the human spectrum.
https://www.theodysseyonline.com/melaninmolecule